Spike's Calculators

# Gable Roof Sheathing

The Gable Roof Sheathing Calculator is designed to help you estimate the amount of plywood needed to cover a gable roof, including accounting for waste. By entering the building length and width in feet and inches, eave and gable overhang in inches, and the roof pitch, you can calculate the total roof area, the number of plywood sheets required, and the additional amount due to waste. The calculation is based on the fact that one sheet of Plywood or OSB (Oriented Strand Board) is a 4' x 8' size. One sheet = 32 ft²

## Gable Roof Sheathing Calculator

Building Length ft inch
Building Width ft inch
Eave Overhang inch
Gable Overhang inch
Roof Pitch : 12
Waste Percentage %

#### Results:

 Roof Area ft² Estimated Plywood Needed # Waste Factor adds # Plywood Needed Including Waste #

#### Calculator

1. enter the building length in feet and inches
2. the building width, the "gable side" in feet and inches
3. gable overhang in inches
4. eave overhang in inches
5. enter the roof pitch as a ratio of rise over 12 inches (e.g., a 6 for a 6:12, etc.)
6. the percentage of waste (default is 10%)

#### Results

1. the area of the roof in square feet
2. the estimated number of 4x8 plywood or OSB sheets required to cover the calculated roof area
3. the extra sheets needed due to waste during installation (e.g., cutting, mistakes, or irregularities in the roof shape). It is calculated based on the specified waste percentage
4. the total number of plywood sheets required for the project, including the waste amount

This calculates the number of sheets needed for a Gable roof.

The square footage of a Hip roof is identical to the square footage of a Gable roof of the same measurements. If you are calculating the number of sheets needed for a Hip roof, then use the eave overhang dimension for the value of the gable overhang, assuming it is the same all around.

The amount of waste on a Hip roof will be higher than for sheathing a Gable roof and even more so if you use OSB sheathing. OSB sheathing has a rough side and a smooth side. You always want to ensure the rough side is up with OSB sheathing. Never install the OSB sheathing with the smooth, slippery side up!